What is XTEN?

XTEN® technology brings the precision of recombinant protein biosynthesis to polymer chemistry. Chemical polymers are manufactured by random polymerization which yields product mixtures of molecules with varying length and sequence. In contrast, XTEN protein polymers are uniform in length and monomer sequence due to the accuracy of ribosomal protein biosynthesis.

What is XTEN

XTEN protein polymers are produced by high-yield microbial expression and purified by industry standard scalable chromatographic methods. XTEN polymers are homogeneous by electrospray ionization mass spectrometry as compared to heterogeneous chemical polymers such as polyethylene glycol (PEG).

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XTEN polymers are composed of chemically stable hydrophilic amino acids and lack secondary structure. Highly hydrophilic XTENs are compatible with both analytical and preparative reverse phase (RP) chromatography. As a result, XTENylated peptides and proteins can be routinely purified and analyzed by RP-HPLC. The example shows that oxidation of a single methionine residue in an XTENylated peptide can be detected and quantitated by C18 RP-HPLC.

XTEN protein polymers are produced by high-yield microbial expression and purified by industry standard scalable chromatographic methods. XTEN polymers are homogeneous by electrospray ionization mass spectrometry as compared to heterogeneous chemical polymers such as polyethylene glycol (PEG).

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Intellectual Property

As patents and other proprietary rights are critical to our business, Amunix has filed patent applications in both the U.S. and other countries to protect the intellectual property rights of our product-specific applications as well as our core technology areas. Amunix has filed comprehensive applications to cover the XTEN platform technology, a broad range of discovery pharmaceuticals enhanced by XTEN, as well as applications in support of our collaborator’s preclinical and clinical development candidates. As of January 1, 2016, Amunix and our collaborators are prosecuting 25 patent families, with 31 issued U.S. and international patents, 8 U.S. and international applications with notice of allowance, and approximately 185 applications pending.